In recent years, the importance of physical fitness has gained popular recognition as part of a healthy life style. Regular exercise is encouraged by society generally as well as government initiatives, including initiatives in schools. There is also a growing realisation amongst employers that a physically fit work force can be an important contributor to bottom line profits, with many companies providing schemes to encourage exercise, including subsidised or free health club membership for example. Physical fitness tends to lead to increased energy, reduced stress, improved efficiency when working and helps maintain health (e.g. reducing the risks of heart disease).
Monitoring physical activity is an important part of any fitness regime. Heart rate monitoring is one form of monitoring that is regularly used. It can be used as a measure of the intensity of physical activity, expressed for example as a percentage of an individual's maximum heart rate (‘HRmax’), and can be used to calculate calories burned during exercise. Maximum heart rate is a well known parameter in the health and fitness industry and there are various well known formula for calculating it. In some cases an individual may monitor their heart rate during exercise to help them maintain a particular effort level relative to their own capabilities.
Heart rate monitors are available in various forms. One common form includes a chest strap transmitter and a wrist worn receiver. The chest strap component uses EKG techniques to detect the heart rate and transmits a signal to the wrist receiver, typically via an analogue radio signal or more recently an ANT+ signal, that displays the measured heart rate in real time to the user. In some health club-based systems, a user's heart rate data might be transmitted to an exercise device that they are using to be displayed to the user on a screen of the exercise device.
Also known are heart rate monitors where the heart rate data is stored temporarily in the wrist receiver, from where it can be uploaded to the user's personal computer in order that they can keep a personal record of their physical activity.